Pretty much build a 7x7 metal (or stone) foundation, then put a behemoth gate where you'd like to bait the Reaper queen, then next to the right side of the gate build 4 pillars up and put ceilings around the sides of the entire foundation, now put 4 on the other side whilst putting 2 in corners and one every other ceiling. Now that your traps set have a pet or lantern with light and hurt the queen till it's really green (bloody) now stop hurting it and wait for a bright pink (from my experience but others say it's red) and wait at the front of the Reaper Queej with a shield.

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